以光照處理綠豆下胚軸組織後，發現組織中生長素 (IAA) 的含量明顯降低，推測可能是分解生長素的速率加快所造成。分解生長素的主要

Two days of light irradiance reduced the levels of endogenous indole-3-acetic acid in mungbean (Phaseolus radiatus) hypocotyls. The important enzymes for IAA metabolic degradation are peroxidases and laccase. Peroxidase activity of mungbean hypocotyls was enhanced sevenfold by light. Laccase activity also remarkably increased after illumination. The lignin content in mungbean hypocotyls were enhanced twofold by light treatment. The inhibition of mungbean hypocotyls growth induced by light might be due to the decline of endogenous IAA, which was degraded by cationic peroxidase. The high level of lignin were correlated with the increased anionic peroxidase activity in light-treated tissues.

誌謝------------------------------------------------1
Chinese abstract----------------------------------2
English abstract-----------------------------------3
Table of contents---------------------------------4
List of tables and figures------------------------5
Introduction ---------------------------------------6
Results ---------------------------------------------8
Discussion-----------------------------------------11
Methods--------------------------------------------14
References ----------------------------------------20
Figures and tables -------------------------------26

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